Slidable carrier or support

ABSTRACT

A thrust bearing has the working surface of a first element facing the working surface of a second element. The material forming the working surface of the first element is made of a harder material than that which forms the working surface of the second element. The working surface of the first element is grooved radially outwardly to the edge so the edges of the grooves will scrape abrasive material from the softer working surface of the softer surface, collect it in the grooves, and discharge it radially out the open ends of the grooves.

United States Patent Tiraspolsky et al.

[151 3,656,823 [451 Apr. 18, 1972 [54] SLIDABLE CARRIER OR SUPPORT [21] App1.No.: 61,055

[52] 11.8. C1 ..308/l60 [51] Int. Cl. ..Fl6c 17/04 [58] Field oiSearch ..308/l60, 168, 162, 161

[56] References Cited UNITED STATES PATENTS 1,121,083 12/1914 De Ferranti ..308/160 1,544,443 6/1925 Gibbs ...308/160 1,792,719 2/1931 White ..308/160 FOREIGN PATENTS OR APPLICATIONS 1,167,356 7/1958 France ..308/160 Primary Examiner--Edgar W. Geoghegan Assistant Examiner-Prank Susko Attorney-Hyer, Eickenroth, Thompson & Turner [57] ABSTRACT A thrust bearing has the working surface of a first element facing the working surface of a second element. The material forming the working surface of the first element is made of a harder material than that which forms the working surface of the second element. The working surface of the first element is grooved radially outwardly to the edge so the edges of the grooves will scrape abrasive material from the softer working surface of the softer surface, collect itin the grooves, and discharge it radially out the open ends of the grooves.

15 Claims, 11 Drawing Figures PATENTEBAPR18 I972 3. 656,823

SHEET 2 BF 2 FIGIO 30 27 Wlddimir Tiraspo/sky Pierre Leschiutta INVENTORS ATTORNEYS SLIDABLE CARRIER R SUPPORT The present invention has general reference to slidable carriers or supports and relates more specially to those which are constituted by elements or materials having different degrees of hardness or elasticity between which a relative alternating, rotary or other motion takes place and lubricated by .means of a fluid capable of carrying away hard or abrasive particles. Such slidable carriers or supports may be constituted for example by the axial thrust bearings of drilling turbines although the invention is not limited to such an industrial use.

Known thrust bearings are generally constituted by a plane metallic disc having a high resistance to abrasion adapted to glide on a ring of shoes made of rubber or another elastomer rigidly carried by a stationary seat, successive shoes thus provided being mutually separated by passages which serve for irrigating the thrust bearing. When the fluid in which such bearing is immersed entrains or carries in suspension hard particles, the latter finally get encrusted into the surface of the elastic shoes and, where they are of abrasive character ultimately bite into the surface of the metal disc.

Such a phenomenon is graphically illustrated by FIGS. 1 to 3 of the accompanying drawings in which FIG. 1 is a partial sectional view of a shoe 1 made of an elastic material subdivided by an irrigation passage or channel 2 and into the surface of which have become encrusted abrasive particles 3 prevailing in a state of suspensions in the irrigating fluid and constituted for example by quartz grains, metal scraps or the like.

FIG. 2 is a partial plane representation while FIG. 3 is a transverse sectional view of a metal disc 4 which rotates in contact with the shoe 1 and has its surface 6 orientated towards said shoe damage by the abrasive particles 3 which scratch said surface, as work is being carried out, and produce furrows 5 therein.

In the showing of FIG. 4 is illustrated another phenomenon which involves a potential disadvantage of known arrangements. In this case, the channel 2 in the shoe 1 is filled up by solid substances shown at 7 such as grains of alkaline chlorides, anhydrous salts or the like which coat the contacting surfaces of the shoe 1 and disc 8 and more particularly the shoe surface. As a result of this, an interruption of the irrigating action takes place which rapidly leads to such a heating effect as will destroy the elastomer.

It has already been proposed to obviate such phenomena by activating the fluid circulation through the interface of the thrust bearings, as indicated in French Pat. No. 1,162,328 and No. 1,167,356. However there are cases when the means proposed to that effect are insufficient for staving off the destructive action of the aforesaid solid particles.

A primary object of the invention is to provide a slidable carrier or support such as an axial thrust bearing of the type comprising elements constituted by materials having different degrees of hardness or elasticity and irrigated by a fluid containing or conveying hard or abrasive particles, said carrier or support being characterized by the fact that its harder element or elements comprise on their surfaces orientated towards the softer elements or elements grooves, flutes, channels or similarly shaped formations that are so disposed and arranged as to scrape off, collect and discharge the hard or abrasive particles from the interface between said harder and softer respective elements of the slidable carrier or support.

Another object of the invention is to provide a single or multiple slidable carrier or support wherein each harder element (made for example of a suitable metal or alloy) is furnished with grooves or flutes that are radially orientated at a suitable angle with respect to a radius or curvilinearly, said grooves being formed in the face or each face of said element in contact with one or several softer elements made for example of a plastic.

A further object of the invention to provide a slidable carrier or support as hereinbefore stated wherein the face or faces of each harder element (made for example of a suitable metal or alloy) in contact with one or several softer elements ofsaid carrier-or support has apertures of'elongated shape in the radial direction at an angle to a radius or curvilinearly merging with one or several channels formed through said element such for example as a disc and terminating in a free edge, for instance along its periphery, whereby each aperture may communicate with an individual channel ending on the periphery of the element or alternatively a free edge or the periphery of said element made of a hard material such as a suitable metal or alloy may have a deep groove into which the aforesaid apertures terminate.

A still further object of the invention is to provide a slidable carrier or support as aforesaid wherein each element made of a hard material maybe made up of two parts adapted to be so assembled as to constitute said element, thereby simplifying the process of manufacture while ensuring owing to appropriate recesses and shoulders a mechanical buttress-like effect of the element periphery.

It will be understood that the arrangement according to the invention permits a sweeping and eventually a scraping action to be obtained on the surface of the softer element that cooperates with the harder element also proper elimination of the ceritrifugally entrained particles to be achieved and eventually an activating effect of the fluid-flow.

The scraping action may be improved, if desired, by combining the grooves, flutes or similar formations with a scraping member, for example in the shape of a rake or brush, adapted to contact with the surface of the softer element. Such a scraping member can be advantageously made of an elastic material possessing a smaller hardness than the surface of the softer .element with which it cooperates.

Yet a further object of the invention is to provide an assembly such as a drilling turbine comprising slidable carriers or supports and particularly axial thrust bearings of the aforesaid type.

With these and such other objects in view as will incidentally appear hereafter, the invention comprises the novel construction and arrangement of parts that will be now fully described with reference to the accompanying drawings illustrating the same and forming a part of the present disclosure.

In the drawings which illustrate the invention as embodied for example in a slidable carrier or support such as an axial thrust bearing including disc-shaped elements:

FIGS. 1 to 4 illustrate the phenomena as hereinbefore analyzed.

FIGS. 5 and 6 are respectively a plan view of an axial bearing disc for a drilling turbine and a partial sectional view of a bearing stage. 1

FIG. 7 is a plan view of a modified disc.

FIG. 8 is a perspective sectional view of a modification.

FIGS. 9 and 10 are sectional views of two further modificatrons.

FIG. 11 is a detail view showing another modification still.

In the showing of FIGS. 5 and 6 is illustrated at 9 the shaft of a drilling turbine carrying a stack of rotor parts comprising metal discs 10 belonging to an axial thrust bearing arranged in alternation with ring members 11. Such an axial rotor thrust bearing cooperates with a stack of stator parts housed in a turbine body 12 and comprising stator elements 15 arranged in alternation with ring members 14, the elements 13 being provided with channels or apertures 15 for axial flow of the fluids and having on their faces shoes 16 made of an elastic material in known fashion. The shoes 16 which are mutually separated by circulation or irrigation channels cooperate with the faces of the discs 10 of the rotor part stack for taking the axial strains in known fashion in the art of drilling turbines.

In the constructional form shown by FIGS. 5 and 6, the metal discs 10 of the rotor stack are provided on their faces which cooperate with the elastic shoes 16 with radial grooves or flutes 17 which terminate on the periphery of the discs. Such grooves or flutes first behave as scrapers, thus entraining the abrasive particles which could become encrusted into the particles and perform their elimination by centrifugal action.

The provision of these grooves or flutes produces a centrifugal activation of the circulation of the irrigating fluid.

In the plan view of FIG. 7 is shown a portion of a disc 18 in whose surface or surfaces are formed grooves or flutes l9 terminating on the disc periphery and having a spirally curved shape. The arrow 20 indicates the direction of rotation of the disc which belongs for example to the rotor part stack of a stage of axial thrust bearing for a drilling turbine. The shape and orientation of the grooves are particularly favorable to centrifugal discharge of the collected particles.

In the embodiment of the invention shown by FIG. 8, the disc 21 has on its faces radially elongated apertures 22 behaving in the same way as the aforesaid grooves or flutes and merging with inner channels or passages 23 terminating on the disc periphery for eliminating the scraped particles that are collected by the apertures 22.

The disc 24 shown inFlG. 9 also has apertures 25 provided in its faces and having a radially elongated shape, said apertures merging with a peripheral groove 26 which provides the desired releasing, eliminating and centrifuging action while lending itself to a relatively simplified construction.

In FIG. is shown an axial thrust bearing disc 27 made up of a pair of half discs 28, 29 providing apertures and channels 30 and performing a mechanical buttress-like action on the disc periphery as a result of the distribution of the recesses and shoulders.

In FIG. 11 is represented a disc 31 similar to the one shown in FIG. 5 and also having in its upper portion a radially extending groove or flute 32 terminating in its periphery. In the present case, a scraping element 33, advantageously made of an elastic material but having a hardness smaller than the one of the elastic surface of the associated shoes while slightly protruding relative to the surface of said disc 31 is located in said groove 32 and held in it by its base portion 34, for instance by means of an adhesive.

It will be seen that the elastic shoes on which the discs glide are at each occurrence systematically swept while eliminating the particles toward the discharge channels. It is moreover apparent from the drawings, especially from FIGS. 8 to 10, that the combination of the centrifugal force and the distribution of irrigating streams will create discharging currents operative in the eliminating channels.

Constructional modifications are conceivable within the field of technical equivalencies. Thus, while there has been shown in the drawings an axial thrust bearing for a conventional drilling turbine, it is obvious that the invention is also applicable to those thrust bearings involving a baffled fluid circulation i.e. in which one and the same fluid successively flows along all contacting surfaces, also to slidable carriers or supports of another type. It will be particularly noted in this respect that substitution of discs according to the invention for usual discs permits by a mere operation of simple nature the aforesaid desirable results to be obtained in connection with slidable carriers or supports or axial thrust bearings of the existing type.

What is claimed is:

1. An axial thrust bearing for use with a lubricating fluid, such as drilling mud, that may have hard or abrasive particles entrained therein, said bearing comprising first and second elements, each having a working surface facing the working surface of the other, said working surface of the first element being made of a relatively hard metallic material, said working surface of the second element being made of an elastomeric material, and means on the working surface of the first element for scraping the working surface of the second element to keep the surface free of embedded hard or abrasive particles entrained in the lubricating fluid flowing between said working surfaces of the elements.

2. The axial thrust bearing of claim 1 wherein the scraping means includes a plurality of recessed formations, each having a generally radially extending trailing edge to scrape such particles from the working surface of the second element.

3. The axial thrust bearing of claim 2 wherein the recessed formations comprise elongated radially extending grooves.

4. The axial thrust bearing of claim 2 wherein the recessed formations comprises grooves extending at an inclination with respect to a radius.

5. The axial thrust bearing of claim 2, wherein the recessed formations comprise arcuate grooves.

6. The axial thrust bearing of claim 2 wherein each recessed formation comprises a generally radially outwardly extending aperture of elongated shape and at least one radially extending channel located in the thickness of said first element and merging with said apertures.

7. The axial thrust bearing of claim 2 wherein the recessed formations comprise apertures of elongated shape and channels formed through the thickness of said first element and terminating on the free edge of said element, each aperture being associated with a channel and merging with said channel.

8. The axial thrust bearing of claim 2 wherein the recessed formations comprise apertures of elongated shape and a deep collecting groove in said first element in which said apertures terminate.

9. The axial thrust bearing of claim 1 comprising several pairs of said first and second elements superimposed for forming a stack in which each first element and each second element has two oppositely directed working surfaces.

10. An axial thrust bearing for use with a lubricating fluid such as drilling mud that may have hard or abrasive particles entrained therein, said bearing comprising a first metal element having a working surface and a free edge and a second element made of an elastomeric material, such as rubber, also having a working surface directed toward the working surface of said first metal element, a plurality of recessed formations located in the working surface of said metal element and merging with said free edge, and a scraping ridge associated with each recessed formation for intercepting and removing said hard or abrasive particles from said working surfaces for collection in and discharge from the recessed formations.

11. A thrust bearing for use in drilling mud that may have hard or abrasive particles entrained therein, said bearing comprising a first element made of a hard metallic material having a working surface and a free edge and a second element made of an elastomeric material having a working surface, said first element being made up of a first half-element having said working surface and formed with recesses providing scraping ridges to scrape any hard or abrasive particles from the drilling mud that is located between the working surfaces or embedded in the elastomeric material of the second element and a second'half-element having a free edge superimposed to the first half-element in opposed relation to said working surface and presenting depressions terminating on the free edge of said second half-element and providing shoulder portions on which said first half-element is abutted.

12. The thrust bearing of claim 11 where the depressions are constituted by grooves.

13. The thrust bearing of claim 11 wherein the depressions are constituted by channels.

14. An axial thrust bearing for use with drilling mud that may have hard or abrasive particles entrained therein, said bearing comprising a first element made of a hard metallic material having a working surface and a free edge, and a second element made of elastomeric material also having a working surface, recessed formations in the working surface of said first element, said formations communicating with the free edge of said first element, and scraping members made an elastic material received in at least some of said recessed formations to scrape the working surface of the second element to remove any of such particles from the mud that collect thereon.

15. An axial thrust bearing for use in a drilling turbine to be lubricated by drilling fluid that may have hard and abrasive particles entrained therein, said bearing comprising a plurality of discs made of a hard metallic material having working surfaces and a free edge, a plurality of shoes made of an elastomeric material, such as rubber, having working surfaces, and recessed formations in the working surfaces of said discs, these fonnations merging with said free edge and having scraping ridges for intercepting and scraping away from between said working surfaces said hard or abrasive particles from the drilling fluid flowing therebetween. 

1. An axial thrust bearing for use with a lubricating fluid, such as drilling mud, that may have hard or abrasive particles entrained therein, said bearing comprising first and second elements, each having a working surface facing the working surface of the other, said working surface of the first element being made of a relatively hard metallic material, said working surface of the second element being made of an elastomeric material, and means on the working surface of the first element for scraping the working surface of the second element to keep the surface free of embedded hard or abrasive particles entrained in the lubricating fluid flowing between said working surfaces of the elements.
 2. The axial thrust bearing of claim 1 wherein the scraping means includes a plurality of recessed formations, each having a generally radially extending trailing edge to scrape such particles from the working surface of the second element.
 3. The axial thrust bearing of claim 2 wherein the recessed formations comprise elongated radially extending grooves.
 4. The axial thrust bearing of claim 2 wherein the recessed formations comprise grooves extending at an inclination with respect to a radius.
 5. The axial thrust bearing of claim 2, wherein the recessed formations comprise arcuate grooves.
 6. The axial thrust bearing of claim 2 wherein each recessed formation comprises a generally radially outwardly extending aperture of elongated shape and at least one radially extending channel located in the thickness of said first element and merging with said apertures.
 7. The axial thrust bearing of claim 2 wherein the recessed formations comprise apertures of elongated shape and channels formed through the thickness of said first element and terminating on the free edge of said element, each aperture being associated with a channel and merging with said channel.
 8. The axial thrust bearing of claim 2 wherein the recessed formations comprise apertures of elongated shape and a deep collecting groove in said first element in which said apertures terminate.
 9. The axial thrust bearing of claim 1 comprising several pairs of said first and second elements superimposed for forming a stack in which each first element and each second element has two oppositely directed working surfaces.
 10. An axial thrust bearing for use with a lubricating fluid such as drilling mud that may have hard or abrasive particles entrained therein, said bearing comprising a first metal element having a working surface and a free edge and a second element made of an elastomeric material, such as rubber, also having a working surface directed toward the working surface of said first metal element, a plurality of recessed formations located in the working surface of said metal element and merging with said free edge, and a scraping ridge associated with each recessed formation for intercepting and removing said hard or abrasive particles from said working surfaces for collection in and discharge from the recessed formations.
 11. A thrust bearing for use in drilling mud that may have hard or abrasive particles entrained therein, said bearing comprising a first element made of a hard metallic material having a working surface and a free edge and a seCond element made of an elastomeric material having a working surface, said first element being made up of a first half-element having said working surface and formed with recesses providing scraping ridges to scrape any hard or abrasive particles from the drilling mud that is located between the working surfaces or embedded in the elastomeric material of the second element and a second half-element having a free edge superimposed to the first half-element in opposed relation to said working surface and presenting depressions terminating on the free edge of said second half-element and providing shoulder portions on which said first half-element is abutted.
 12. The thrust bearing of claim 11 where the depressions are constituted by grooves.
 13. The thrust bearing of claim 11 wherein the depressions are constituted by channels.
 14. An axial thrust bearing for use with drilling mud that may have hard or abrasive particles entrained therein, said bearing comprising a first element made of a hard metallic material having a working surface and a free edge, and a second element made of elastomeric material also having a working surface, recessed formations in the working surface of said first element, said formations communicating with the free edge of said first element, and scraping members made an elastic material received in at least some of said recessed formations to scrape the working surface of the second element to remove any of such particles from the mud that collect thereon.
 15. An axial thrust bearing for use in a drilling turbine to be lubricated by drilling fluid that may have hard and abrasive particles entrained therein, said bearing comprising a plurality of discs made of a hard metallic material having working surfaces and a free edge, a plurality of shoes made of an elastomeric material, such as rubber, having working surfaces, and recessed formations in the working surfaces of said discs, these formations merging with said free edge and having scraping ridges for intercepting and scraping away from between said working surfaces said hard or abrasive particles from the drilling fluid flowing therebetween. 